Change enctype when submitting a form

Question

Hi,
Can anyone please let me know if its possible to change the enctype when submitting a form. I am trying to change the enctype to "multipart/form-data" when upload is clicked, else i want it to be the default.....
function OnSubmitForm(myform)
alert('document.pressed : ' + document.pressed );
if(document.pressed == 'Upload')
myform.enctype="multipart/form-data";
alert('enctype: ' + myform.enctype);
else
alert('enctype: ' + myform.enctype);
return true;
}

Answer 1

The JavaScript property is encoding (not enctype). The JavaScript encoding form property corresponds to the html enctype form attribute. So the code should be:
function OnSubmitForm(myform)
alert('document.pressed : ' + document.pressed );
if(document.pressed == 'Upload')
myform.encoding="multipart/form-data";
alert('enctype: ' + myform.encoding);
else
alert('enctype: ' + myform.encoding);
return true;
}